The present invention relates generally to a machine for automatically driving threaded fasteners such as screws into a suitable workpiece. More particularly, the invention relates to such a machine which is substantially self-contained and includes a replaceable magazine for supplying successive fasteners.
The prior art has provided a substantial number of automatic screwdrivers or machines which are power operated for driving threaded fasteners into engagement with a workpiece. With the screwdrivers or machines being fluid-operated, for example, by a source of air under pressure, threaded fasteners are commonly provided from a remote location through a delivery tube or the like to be received within the machine in engagement with a rotatable drive means or bit for driving the fastener into the workpiece.
The prior art has also provided a number of push-to-start automatic screwdrivers or similar machines for threaded fasteners wherein operation of a drive motor is actuated by the pressure of engagement between the threaded fastener and the workpiece.
More recently, the prior art has also provided fastener machines including self-contained magazines or cartridges for supplying screws or fasteners into engagement with a rotary drive means. Usually, these machines are manually actuated by a trigger or the like in order to commence rotation of the fastener for engaging it with the workpiece.
As is apparent from the preceding description, fastener machines of the type referred to herein are most commonly used with threaded fasteners in the form of screws. A workpiece may for example be formed with a tapped or untapped opening for receiving the threaded fastener. However, it is also contemplated by the invention that the machine could be of a self-tapping type wherein the threaded fastener forms an opening in the workpiece for receiving the threaded fastener.
The invention contemplates such machines for driving other types of threaded fasteners besides screws into engagement with a workpiece. For example, the threaded fastener could be in the form of a bolt or even a threaded nut, the workpiece then being in the form of a threaded shank for receiving the nut. In any event, the invention is to be generally construed in terms for applying any of a variety of threaded fasteners to a suitable workpiece.
In connection with the engagement of such a variety of threaded fasteners to suitable workpieces, it is desirable in many applications to provide a machine suitable for driving fasteners in rapid succession. Accordingly, there has been found to remain a need for an automatic machine for applying threaded fasteners or the like which is capable of overcoming various limitations of the prior art as summarized above.